Congestion Control for Real - Time Tra c in High - Speed NetworksHenning

Traditional feedback congestion control is not suitable for high-speed networks due to their high bandwidth-to-delay ratio. In this paper, we investigate the possibility of locally controlling short-term congestion for loss-tolerant, but delay-sensitive traac such as packet voice through selective discarding of packets based on the virtual work found by a packet on arrival to a queue (local deadlines). By analysis and simulation of a multi-stage virtual circuit it is shown that this approach can cut voice-tolerable loss rates in half for high loads. Further, we show that the simple case of using the same local deadline throughout the network performs nearly as well as taking reduced interior traac into consideration and optimizing loss performance over a set of heterogeneous local deadlines. By example, the issue of establishing control parameters at call setup time is also considered.